1. Field of the Invention
The present invention relates to an improvement of a rolling device.
2. Description of the Related Art
In a rolling device including a pair of transfer grooves and a plurality of rolling elements inserted between the transfer grooves, individual rolling elements rotate in the same direction, which means that rolling element surfaces adjacent to each other move in opposite directions. As a result, large sliding friction is caused by contact between the rolling elements, if the rolling device does not have a supporting cage.
To ease this problem, it is a common practice to use a supporting cage for retaining the rolling elements at uniform intervals (see Patent Document 1, for example).
Patent Document 1: Japanese Unexamined Patent Publication No. 2005-163997